Calamities of Nature is a webcomic that frequently has skeptical and scientifiic themes. A recent one deals with ghosts and the soul, and it hits on a message I've said many times: there's no such thing as the supernatural. Either something is natural -- that is, part of the Universe -- or else it doesn't exist. If you posit some thing that has no perceivable or measurable effect, then it may as well not exist. And as soon as you claim it does have an effect -- it can be seen, heard, recorded, felt -- then it must be in some way testable, and therefore subject to science. You can't claim ghosts are supernatural, beyond the realm of science, but also claim they show up on a freaking thermal camera! Well, you can claim that, but you'd be wrong. So there you go.
[NOTE: In a funny coincidence, after I drafted this post but before I published it, my fellow Hive Overmind blogger Sean Carroll posted a link to this same cartoon using almost exactly the same post title! COINCIDENCE? Well, yeah, actually. Great minds and all that. I'll add we chose different panels of the comic to post though.]